Related by context. Frequent words. (Click for all words.) 69 Sputnik 55 Yuri Gagarin 54 lunar orbiter 51 manned spacecraft 50 robotic spacecraft 50 spacecraft 48 lunar probe 48 Chandrayaan 48 unmanned spacecraft 48 lunar landing 46 orbiting 46 Soyuz rocket 46 Gagarin 46 spaceship 46 remote sensing satellite 45 NASA Deep Impact 45 astronaut Yang Liwei 45 space shuttle 45 manned spaceflight 45 Sputnik moment 44 lunar exploration 44 Dennis Tito 44 spacecrafts 44 shuttle Challenger 44 Challenger exploded 44 Mercury Gemini 44 moon landings 44 cryogenic engine 44 Skylab 43 blastoff 43 Tunguska 43 Johannes Kepler 43 Satish Dhawan Space 43 Space Shuttle Discovery 43 Taepodong 43 suborbital flight 43 Automated Transfer Vehicle 43 spaceflight 42 orbited 42 orbit 42 Baikonur Cosmodrome 42 Chang'e 42 Shenzhou VII 42 GSLV 42 SpaceShipOne 42 Huygens probe 42 moon 42 Orion spacecraft 42 International Space Station 42 human spaceflight 42 outer space 42 Soyuz capsule 41 Hubble telescope 41 lunar rover 41 Korolyov 41 Space Agency 41 lunar surface 41 von Braun 41 sub orbital 41 comet Wild 41 Lunar Crater Observation 41 Soviets 41 Shenzhou 41 remote sensing satellites 41 Baikonur space 41 shuttle Atlantis 41 Yang Liwei 41 manned missions 41 Astronauts aboard 41 satellites 41 Planetary Society 41 scramjet 41 Alan Shepard 40 Deep Impact spacecraft 40 Orbital Sciences Corporation 40 NASA 40 Shenzhou VI 40 lunar orbit 40 NASA Cassini spacecraft 40 space shuttle Discovery 40 moonshot 40 lander 40 orbiter 40 Hubble Space Telescope 40 lunar 40 Soviet Union 40 lunar module 40 flying saucer 40 Soyuz 40 Sensing Satellite 40 Ansari X 40 Earth orbit 39 CryoSat 39 Saturn V 39 lunar missions 39 Kourou 39 moon Titan 39 Laika 39 flyby 39 telescope 39 cosmonaut